There are a number of conditions for patients where it is desirable to accurately position a probe, catheter, or other device within a brain of a patient by passing the device through a burr hole or other opening in the cranium of the patient. Intracranial probes include deep brain stimulating electrodes, recording electrodes, optical probes, and dialysis probes. Intracranial catheters include fiber optic catheters, injection cannulae, aspiration cannulae and fluid shunts. These intracranial devices are generally inserted through a burr hole during neurosurgery utilizing a guide system involving MRI (Magnetic Resonance Imaging), CT (Computed Tomography), or a stereotactic instrument, and are intended for positional placement in relation to selected anatomy of the patient. Many such intracranial devices are secured in place during or after surgery for use over an extended period of time and require accurate and reliable fixation in relation to the initial placement and patient anatomy.
Reliable fixation is essential to successful treatment utilizing intracranial devices such as electrodes or electrical probes which may have a dramatically different therapeutic effect if their position within a brain is shifted by only a few millimeters. Shunts and other catheters can become rapidly blocked or gradually occluded if intake ports are moved into an unintended position against existing tissue or are moved too close to dynamic cell layers such as found in choroid plexus.
A number of currently available fixation devices are complex, time-consuming to implement, overly high-profile with poor cosmetic results, and/or prone to failure. Several brain lead anchoring systems are disclosed by Ray in U.S. Pat. No. 4,328,813 and by Dreessen et al. in U.S. Pat. No. 5,464,446. Other anchoring systems are described by Knuth et al. in U.S. Pat. No. 5,865,842 and by Baudino in U.S. Pat. No. 6,044,304. Alternative anchor systems are discussed by Gerber et al. in U.S. Patent Pub. No. 2011/0190857 and by Swoyer et al. in U.S. Patent Pub. No. 2012/0232627, for example.
It is therefore desirable to have a simple, secure, reliable device to hold intracranial devices fixedly in a selected position.